If a patient with neutropenia presents with fever, perform an infection workup, including blood cultures for anaerobic and aerobic organisms. Obtain two sets of blood culture samples, 10-15 minutes apart, from peripheral veins; obtain samples from each port of a catheter if the patient has central venous access.
Other laboratory studies used for a complete fever workup include the following:
Urine culture and sensitivity
Culture of wound or catheter discharge
Sputum Gram stain and culture
Stool for Clostridium difficile
Skin biopsy, if new erythematous and tender skin lesions are present
Broad-spectrum antibiotics should be started within 1 hour of cultures.
Tests for antineutrophil antibodies should be performed in patients with a history suggestive of autoimmune neutropenia and in those with no other obvious explanation for the agranulocytosis. Various methods for detecting antineutrophil autoantibodies have different limitations; therefore, more than one assay method is recommended. In addition, data are limited on false-negative results, and, thus, only a positive test is likely meaningful.
No specific imaging study establishes the diagnosis of agranulocytosis. As part of the workup for localization of infection, appropriate x-rays (eg, chest images) are indicated. Other imaging studies are determined by the specific circumstances of each case. Perform long-bone x-rays if a form of congenital neutropenia is suspected. If the neutropenic patient is febrile, obtain a posterior-anterior and lateral chest x-ray to assess for signs of pneumonia. Obtain liver-spleen radionuclide scans if the presence of splenomegaly and splenic sequestration are suspected in a patient with neutropenia. This study also allows evaluation of hepatocellular function and colloid shift, which occurs when hypersplenism is caused by cirrhosis with portal hypertension.
Bone marrow may show myeloid hypoplasia or absence of myeloid precursors. In many cases, the bone marrow is cellular with a maturation arrest at the promyelocyte, myelocyte, or even band neutrophil stage of maturation. This latter finding is common in drug-induced and immune neutropenias, as the destruction may be selective of the more mature neutrophils only.
For more on the workup of neutropenia, read here.
Medscape © 2017 WebMD, LLC
Any views expressed above are the author's own and do not necessarily reflect the views of WebMD or Medscape.
Cite this: Elwyn C. Cabebe. Fast Five Quiz: How Much Do You Know About Neutropenia? - Medscape - Nov 22, 2017.